For those looking for casters that may also be a solid base, I have four of these leftover (i.e. available for sale) from a project where I mis-underestimated some dimensions. Rolls well enough on a garage floor, all four swivel, and you just spin the red dial a few turns to raise it off the wheel. The larger ones are supposedly good for 2200 lbs for the set. It's a Chinesium copy of a proper industrial product, but so far so good and of course budget-friendly. Don't know that I would mount an anvil stand onto them, but a static load should be fine.

Full size
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And its little brother mounted to the bottom of a 4x4
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